When Eve Ensler was 5, her father started sexually abusing her at night while she lay in bed. As she grew older, he began beating her. She developed strange infections, suffered night terrors and began drinking.

Eventually, she broke away, and in 1996 she wrote The Vagina Monologues, one of the most celebrated plays of the 20th century. But before that, her father did everything he could to undermine her, humiliate her, poison her.

The Apology contains the words that writer Eve Ensler says she needed to hear her abusive father say.

(Bloomsbury)

Although Ensler knew he never would, she waited for him to say he was sorry. Even after he died, she kept waiting.

Until now.

The Apology contains the words that Ensler needed to hear her father say. It's a slim book of unbearable heft. The text is presented as a letter written by her father from a kind of void beyond the grave, "floating, unmoored, spinning." He candidly describes the atrocities he committed, he confesses the weakness that made him so cruel, and he acknowledges the damage he wrought on her tender mind and body.

The Apology is not a creation of psychological realism so much as an act of therapeutic imagination. For Ensler, now 65, writing out these sentences brought freedom — finally.

Talking to me from her home in New York, she broke down briefly as she tried to describe just how different the world suddenly feels.

"I don't even know what this place is going to be now," she says, her tears turning to laughter. "My heart feels so open in a way it hasn't been able to be open. It's like driving a new car — I don't know how to drive this car!"

Ensler had been trapped in an internal dialogue with her father every day for decades. Then, in one intense four-month period, she wrote morning and night until the book was done.

"It takes so long to get to a place where you can open yourself to feel what your perpetrator feels," she says, "and to know what they've been through, to know who they are because it's so much easier and less painful to cast them as a kind of monolithic monster."

As difficult as The Apology is to read, it was infinitely harder to write. "I didn't want to climb into my father," Ensler admits. "I didn't want to know what was inside my father. It was too painful."

That process involved thinking deeply about the way her abuser was raised and acculturated in what she calls the "rape paradigm." His own parents, following the brutal child-rearing advice of a popular German physician, were severe and unaffectionate. Her father was taught to be strong and proud, charming rather than loving. Any expressions of vulnerability or regret were signs of weakness to be repressed in himself, scorned in others.

But Ensler isn't letting her father — or any abuser — off the hook. "I needed to understand what led my father to do what he did in order to make sense of it," she says. "I didn't feel like it was justification. I felt like it was explanation."

The Apology may be a very personal act of therapeutic recovery for the author, but Ensler also offers it as a model for others. Most abused women, after all, will never hear an expression of sorrow from their tormentors. Ensler hopes victims can experience a degree of healing by writing the letter they need to hear. That process is already in use at City of Joy, a women's center Ensler founded in the Congo. "We can actually shift the way those predators live inside us," she says, "and move them inside us from a monster to an apologist."

But she has a very different audience in mind for The Apology, too: men.

A couple of years into the #MeToo era, she's yet to hear what she thinks needs to be said.

"We've told our stories. We've broken the silence. A few men have lost their jobs (but seem to be getting them back fairly quickly). Some have gone to prison. But I really haven't heard one man make a true, thorough, public accounting: an apology for what he's done, reflecting any self-interrogation, reflecting that he went back into therapy or worked with his clergy or looked into himself to figure out what the seeds of this are."

For those men — the famous and the unknown — The Apology is a blueprint of contrition.

It's surprising for one of America's most famous playwrights to turn to prose instead of drama, but Ensler says she needed the isolation of a book to get her story down. Someday, though, she'd like to see it performed as a monologue on the stage.

The audiobook version of The Apology moves in that direction. Ensler has vowed never to read publicly from the book, so it's narrated by Edoardo Ballerini, who won the Audie Award for best male narrator earlier this year. He found the process of inhabiting the mind of Ensler's father devastating. At points, he couldn't help weeping as he read.